[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) › Cerebellum [Nervous system](https://durgical.com/en/anatomy/system/nervous-system/) · [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) # Cerebellum The cerebellum is the 'little brain' at the back of the head below the cerebrum; it coordinates movement, balance and timing, and damage makes movement clumsy. Official name: Anterior quadrangular lobule [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=head_neck&select=cerebellum&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The 'little brain' at the back below the cerebrum, with finely folded hemispheres. ## What it does Coordinates movement, balance and timing; damage makes movements clumsy (ataxia). ## Key points - Signs are on the same side as the lesion: its output crosses in the [midbrain](https://durgical.com/en/anatomy/midbrain/) and the corticospinal tract crosses back - Signs: dysmetria (past-pointing), intention tremor, dysdiadochokinesia, nystagmus, scanning speech, hypotonia and a broad-based, unsteady gait - Three functional parts: vestibulocerebellum (flocculonodular lobe: balance, eye movements), spinocerebellum ([vermis](https://durgical.com/en/anatomy/central-lobule/) and paravermis: trunk and limbs), cerebrocerebellum (lateral hemispheres: planning) - Purkinje cells are the only output of the cortex and are inhibitory; they act through the deep nuclei: dentate, emboliform, globose, fastigial (lateral to medial) ## Key facts **Where** Posterior cranial fossa under the tentorium **Blood supply** SCA, AICA, PICA **Function** Coordination, balance, motor learning (same side of the body) ## Relations **Above** [Tentorium cerebelli](https://durgical.com/en/anatomy/tentorium-cerebelli/), and above it the occipital lobes **In front** [Fourth ventricle](https://durgical.com/en/anatomy/fourth-ventricle/), [pons](https://durgical.com/en/anatomy/pons/) and [medulla oblongata](https://durgical.com/en/anatomy/medulla-oblongata/), joined to them by the three [cerebellar peduncles](https://durgical.com/en/anatomy/superior-cerebellar-peduncle/) **Lateral** [Sigmoid sinus](https://durgical.com/en/anatomy/sigmoid-sinus/) and the back of the petrous [temporal bone](https://durgical.com/en/anatomy/temporal-bone/); the facial and vestibulocochlear nerves at the cerebellopontine angle **Behind** [Occipital bone](https://durgical.com/en/anatomy/occipital-bone/) of the posterior cranial fossa, with the transverse sinuses and the [confluence of sinuses](https://durgical.com/en/anatomy/confluence-of-sinuses/) **Below** [Cerebellar tonsils](https://durgical.com/en/anatomy/tonsil-of-cerebellum/) above the [foramen magnum](https://durgical.com/en/anatomy/foramen-magnum/) and the cisterna magna ## How to find it Fills the posterior fossa below the tentorium, behind the pons and medulla, roofing the fourth ventricle. On the skull its upper limit follows the [transverse sinus](https://durgical.com/en/anatomy/transverse-sinus/) from the inion toward the mastoid (superior nuchal line), the landmark for suboccipital openings. Its tonsils lie beside the medulla above the foramen magnum; a tonsil tip over about 5 mm below it on sagittal MRI suggests Chiari I. ## Examination - Finger-to-nose: the finger overshoots (dysmetria) and shakes more as it nears the target (intention tremor) - Heel-to-shin: the heel wavers off the shin; mainly tests the legs and the anterior vermis - Rapid alternating movements (patting the hand palm up, palm down): slow, irregular rhythm is dysdiadochokinesia - Tandem gait: falling to one side on heel-to-toe walking; Romberg test is usually negative, as the unsteadiness is present with the eyes open ## On imaging MRI is the study of choice; on CT the posterior fossa is blurred by streak artefact from the dense skull base. A swollen cerebellar infarct can be seen compressing the fourth ventricle. ## Common problems - Cerebellar stroke or bleeding: sudden dizziness, vomiting and inability to walk. - Alcohol and some medicines impair it: unsteady walking, slurred speech. ## How it is diagnosed Coordination tests (finger-to-nose, heel-to-shin); CT or MRI. ## Treatment - Treat the cause; surgery to relieve pressure for large strokes or bleeds; balance rehabilitation. ## Clinical notes - Medulloblastoma, the most common malignant brain tumour in children, arises in the midline cerebellum and can spread through the CSF - Pilocytic astrocytoma of childhood typically forms a cyst with a nodule in a cerebellar hemisphere; haemangioblastoma is the adult cerebellar tumour linked to von Hippel–Lindau disease - A large cerebellar infarct or bleed can swell, block the fourth ventricle and compress the brainstem; suboccipital decompression may be lifesaving - Otogenic cerebellar abscess: middle ear and mastoid infection can spread through the thin posterior surface of the petrous bone or along a thrombosed sigmoid sinus into the adjacent cerebellar hemisphere ## Development Grows from the dorsal part of the metencephalon (the rhombic lips) and keeps developing after birth. Chiari II and Dandy–Walker malformations are hindbrain anomalies that often come with hydrocephalus. ## Memory aid Cerebellar signs: DANISH (Dysdiadochokinesia, Ataxia, Nystagmus, Intention tremor, Scanning speech, Hypotonia). Deep nuclei, lateral to medial: 'Don't Eat Greasy Food'. ## Related conditions - [Maple syrup urine disease](https://durgical.com/en/conditions/maple-syrup-urine-disease/) - [Congenital disorder of glycosylation type Ia (PMM2-CDG)](https://durgical.com/en/conditions/congenital-disorder-of-glycosylation-type-ia/) - [Sandhoff disease](https://durgical.com/en/conditions/sandhoff-disease/) - [Ataxia-telangiectasia](https://durgical.com/en/conditions/ataxia-telangiectasia/) - [Prion diseases (Creutzfeldt–Jakob)](https://durgical.com/en/conditions/prion-diseases/) - [Mercury poisoning](https://durgical.com/en/conditions/mercury-poisoning/) - [Menkes disease](https://durgical.com/en/conditions/menkes-disease/) - [Intracerebral haemorrhage](https://durgical.com/en/conditions/intracerebral-haemorrhage/) - [Acute alcohol (ethanol) intoxication](https://durgical.com/en/conditions/acute-alcohol-intoxication/) - [Anticonvulsant toxicity (phenytoin, carbamazepine, valproate)](https://durgical.com/en/conditions/anticonvulsant-toxicity/) - [Rabies](https://durgical.com/en/conditions/rabies/) - [Essential tremor](https://durgical.com/en/conditions/essential-tremor/) - [Brain metastases](https://durgical.com/en/conditions/brain-metastases/) - [Childhood brain tumours (medulloblastoma, pilocytic astrocytoma, craniopharyngioma)](https://durgical.com/en/conditions/childhood-brain-tumours/) - [Friedreich ataxia](https://durgical.com/en/conditions/friedreich-ataxia/) - [Multiple system atrophy (MSA)](https://durgical.com/en/conditions/multiple-system-atrophy/) - [Spinocerebellar ataxias (autosomal dominant ataxias)](https://durgical.com/en/conditions/spinocerebellar-ataxias/) - [Alcohol use disorder](https://durgical.com/en/conditions/alcohol-use-disorder/) - [Autism spectrum disorder (ASD)](https://durgical.com/en/conditions/autism-spectrum-disorder/) - [Cannabis use disorder](https://durgical.com/en/conditions/cannabis-use-disorder/) - [Lithium toxicity](https://durgical.com/en/conditions/lithium-toxicity/) ## Test yourself Think of the answer, then tap the question to see it. ## On which side of the body do cerebellar signs appear? On the same side as the lesion, because its output crosses in the midbrain and the corticospinal tract crosses back. ## What are the classic cerebellar signs? Dysmetria, intention tremor, dysdiadochokinesia, nystagmus, scanning speech, hypotonia and a broad-based unsteady gait. ## What does the finger-to-nose test show in cerebellar disease? The finger overshoots (dysmetria) and shakes more as it nears the target (intention tremor). ## Why is the Romberg test usually negative in cerebellar ataxia? The unsteadiness is present with the eyes open too, so closing them adds little. ## Which is the most common malignant brain tumour in children, and where does it arise? Medulloblastoma, in the midline cerebellum; it can spread through the CSF. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/anatomy/anterior-quadrangular-lobule/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** lobulus quadrangularis anterior TA2 5808 **Official Spanish (DeCS)** Cerebelo DeCS D002531 **English (TA2)** Anterior quadrangular lobule ## Related - [Fourth ventricle](https://durgical.com/en/anatomy/fourth-ventricle/) - [Cerebellar arteries](https://durgical.com/en/anatomy/superior-cerebellar-artery/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=2568); [Neuroanatomy, Cerebellum](https://www.ncbi.nlm.nih.gov/books/NBK538167/); [13.1 The Embryologic Perspective](https://openstax.org/books/anatomy-and-physiology-2e/pages/13-1-the-embryologic-perspective) (OpenStax (Rice University), 2022) · adapted, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/); [13.2 The Central Nervous System](https://openstax.org/books/anatomy-and-physiology-2e/pages/13-2-the-central-nervous-system) (OpenStax (Rice University), 2022) · adapted, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/); Tratado de anatomía humana (9.ª ed.), tomo II, Libro V, sección 2 (Encéfalo), capítulos I-V: bulbo, protuberancia, cerebelo, cuarto ventrículo, mesencéfalo. ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/anterior-quadrangular-lobule/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/anterior-quadrangular-lobule/